content: /* Copyright 2016 The TensorFlow Authors. All Rights Reserved.
  
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
  
      http://www.apache.org/licenses/LICENSE-2.0
  
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
  ==============================================================================*/
  
  package org.tensorflow.op.core;
  
  import static org.junit.Assert.assertArrayEquals;
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertTrue;
  
  import java.io.ByteArrayOutputStream;
  import java.io.DataOutputStream;
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.nio.DoubleBuffer;
  import java.nio.FloatBuffer;
  import java.nio.IntBuffer;
  import java.nio.LongBuffer;
  
  import org.junit.Test;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  import org.tensorflow.Graph;
  import org.tensorflow.Session;
  import org.tensorflow.Tensor;
  import org.tensorflow.op.Scope;
  
  @RunWith(JUnit4.class)
  public class ConstantTest {
    private static final float EPSILON = 1e-7f;
    
    @Test
    public void createInt() {
      int value = 1;
      
      try (Graph g = new Graph();
          Session sess = new Session(g)) {
        Scope scope = new Scope(g);
        Constant<Integer> op = Constant.create(scope, value);
        try (Tensor<Integer> result = sess.runner().fetch(op).run().get(0).expect(Integer.class)) {
          assertEquals(value, result.intValue());
        }
      }
    }
  
    @Test
    public void createIntBuffer() {
      int[] ints = {1, 2, 3, 4};
      long[] shape = {4};
  
      try (Graph g = new Graph();
          Session sess = new Session(g)) {
        Scope scope = new Scope(g);
        Constant<Integer> op = Constant.create(scope, shape, IntBuffer.wrap(ints));
        try (Tensor<?> result = sess.runner().fetch(op).run().get(0)) {
          int[] actual = new int[ints.length];
          assertArrayEquals(ints, result.expect(Integer.class).copyTo(actual));
        }
      }
    }
  
    @Test
    public void createFloat() {
      float value = 1;
      
      try (Graph g = new Graph();
          Session sess = new Session(g)) {
        Scope scope = new Scope(g);
        Constant<Float> op = Constant.create(scope, value);
        try (Tensor<?> result = sess.runner().fetch(op).run().get(0)) {
          assertEquals(value, result.expect(Float.class).floatValue(), 0.0f);
        }
      }
    }
  
    @Test
    public void createFloatBuffer() {
      float[] floats = {1, 2, 3, 4};
      long[] shape = {4};
  
      try (Graph g = new Graph();
          Session sess = new Session(g)) {
        Scope scope = new Scope(g);
        Constant<Float> op = Constant.create(scope, shape, FloatBuffer.wrap(floats));
        try (Tensor<?> result = sess.runner().fetch(op).run().get(0)) {
          float[] actual = new float[floats.length];
          assertArrayEquals(floats, result.expect(Float.class).copyTo(actual), EPSILON);
        }
      }
    }
  
    @Test
    public void createDouble() {
      double value = 1;
      
      try (Graph g = new Graph();
          Session sess = new Session(g)) {
        Scope scope = new Scope(g);
        Constant<Double> op = Constant.create(scope, value);
        try (Tensor<?> result = sess.runner().fetch(op).run().get(0)) {
          assertEquals(value, result.expect(Double.class).doubleValue(), 0.0);
        }
      }
    }
  
    @Test
    public void createDoubleBuffer() {
      double[] doubles = {1, 2, 3, 4};
      long[] shape = {4};
  
      try (Graph g = new Graph();
          Session sess = new Session(g)) {
        Scope scope = new Scope(g);
        Constant<Double> op = Constant.create(scope, shape, DoubleBuffer.wrap(doubles));
        try (Tensor<?> result = sess.runner().fetch(op).run().get(0)) {
          double[] actual = new double[doubles.length];
          assertArrayEquals(doubles, result.expect(Double.class).copyTo(actual), EPSILON);
        }
      }
    }
  
    @Test
    public void createLong() {
      long value = 1;
      
      try (Graph g = new Graph();
          Session sess = new Session(g)) {
        Scope scope = new Scope(g);
        Constant<Long> op = Constant.create(scope, value);
        try (Tensor<?> result = sess.runner().fetch(op).run().get(0)) {
          assertEquals(value, result.expect(Long.class).longValue());
        }
      }
    }
  
    @Test
    public void createLongBuffer() {
      long[] longs = {1, 2, 3, 4};
      long[] shape = {4};
  
      try (Graph g = new Graph();
          Session sess = new Session(g)) {
        Scope scope = new Scope(g);
        Constant<Long> op = Constant.create(scope, shape, LongBuffer.wrap(longs));
        try (Tensor<?> result = sess.runner().fetch(op).run().get(0)) {
          long[] actual = new long[longs.length];
          assertArrayEquals(longs, result.expect(Long.class).copyTo(actual));
        }
      }
    }
  
    @Test
    public void createBoolean() {
      boolean value = true;
      
      try (Graph g = new Graph();
          Session sess = new Session(g)) {
        Scope scope = new Scope(g);
        Constant<Boolean> op = Constant.create(scope, value);
        try (Tensor<?> result = sess.runner().fetch(op).run().get(0)) {
          assertEquals(value, result.expect(Boolean.class).booleanValue());
        }
      }
    }
  
    @Test
    public void createStringBuffer() throws IOException {
      byte[] data = {(byte) 1, (byte) 2, (byte) 3, (byte) 4};
      long[] shape = {};
  
      // byte arrays (DataType.STRING in Tensorflow) are encoded as an offset in the data buffer,
      // followed by a varint encoded size, followed by the data.
      ByteArrayOutputStream baout = new ByteArrayOutputStream();
      DataOutputStream out = new DataOutputStream(baout);
      // Offset in array.
      out.writeLong(0L);
      // Varint encoded length of buffer.
      // For any number < 0x80, the varint encoding is simply the number itself.
      // https://developers.google.com/protocol-buffers/docs/encoding#varints
      assertTrue(data.length < 0x80);
      out.write(data.length);
      out.write(data);
      out.close();
      byte[] content = baout.toByteArray();
  
      try (Graph g = new Graph();
          Session sess = new Session(g)) {
        Scope scope = new Scope(g);
        Constant<String> op = Constant.create(scope, String.class, shape, ByteBuffer.wrap(content));
        try (Tensor<?> result = sess.runner().fetch(op).run().get(0)) {
          assertArrayEquals(data, result.expect(String.class).bytesValue());
        }
      }
    }
  }
  